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Cisco MGX 8850 Routing Switch Command Reference
Release 2.0, Part Number 78-10467-04 Rev C0, October 2001
Chapter 5
PNNI Commands
cnfpnni-link-selection
cnfpnni-link-selection
Configure PNNI Link Selection
—
specify the routing policies for parallel links.
The cnfpnni-link-selection command specifies which routing policies are used to select one of the
parallel links that connect a neighboring PNNI node. Neighboring node in this case means a directly
connected node. The cnfpnni-link-selection command applies only if parallel links exist between the
specified port and neighboring nodes.
Cards on Which This Command Runs
PXM45
Syntax
cnfpnni-link-selection <portid>
{minaw | maxavcr | maxcr | loadbalance}
Syntax Description
portid
The portid is the PNNI physical port. The format is
[shelf.]slot[:subslot].port[:subport]. See also
PNNI Format, page 5-5
.
Default: no default port ID
minaw
The routing protocol selects the link with the least administrative weight (AW).
The AW is a numeric value that every logical port ingress has. The total cost of a
route is the sum of all ingress port AWs in both directions of the route.
The minaw policy is the default.
maxavcr
The routing protocol selects the link with the largest available cell rate (AvCR).
The AvCR is the remaining bandwidth after the total utilized bandwidth is
subtracted from the maximum cell rate (MaxCR).
The maxavcr policy works well for traffic that consistently requires a large
amount of bandwidth.
maxcr
The routing protocol selects the link with the largest maximum cell rate (MaxCR).
Typically, the MaxCR is the maximum speed of the line (or trunk). Therefore, if
one link traverses an OC3 line and another link traverses a T3 line, the MaxCR
policy dictates that PNNI select the OC3 line. Only when sufficient bandwidth
does not exist on a line does the routing protocol switch to AvCR.
The maxcr policy works well for bursty traffic.
loadbalance
The routing protocol alternates the link it selects for routing new calls. The load
balance policy works well with links that have identical or very similar AW or
bandwidth characteristics.